1. Field of the Invention
The present invention relates to a resin amount measuring method and device that measures an amount of resin impregnated in a fiber in a filament winding molding.
2. Description of the Related Art
A filament winding apparatus is configured by a fiber supply unit, a resin impregnating unit that impregnates resin in the fiber, a winding unit that winds the fiber to a member to be wound, and the like. It is known to arrange a device that measures the resin impregnated amount with respect to the fiber between the resin impregnating unit and the winding unit, and to feedback the measurement result to the resin impregnating unit, as is described in Japanese Laid-Open Patent Publication No. 2004-209923 and the like. Here, the weight of a predetermined length of the fiber after the resin impregnating unit is measured, and the resin impregnated amount is measured based on the measurement result. Specifically, a fiber of a predetermined length is pulled out from the resin impregnating unit, and the weight thereof is measured with both ends of the fiber in a supported state.
A filament winding molded article with satisfactory quality can be stably obtained while maintaining the resin impregnated amount with respect to the fiber in a predetermined constant range by feedback controlling the resin impregnating unit as described above. Production of defective goods can be suppressed since impregnation failure is detected before winding the fiber to the member to be wound.
However, in the mode of Japanese Laid-Open Patent Publication No. 2004-209923, the fiber needs to be gripped to measure the weight, and thus it is difficult to continuously perform the measurement without stopping the flow of fiber, and higher speed of the filament winding molding cannot be responded. Furthermore, since a gripping member and a load measuring instrument of the weight measuring unit contact the fiber, the resin transfers to the gripping member and the like, whereby the resin content may vary.
In addition, taking into consideration that it is extremely difficult to constantly support both ends of the fiber with a constant force, and that the amount of resin impregnated in the fiber in this type of filament winding molding is an extremely small amount of about 0.5 g/m, a slight error in the supporting force greatly influences the measurement value of the resin impregnated amount, and it is practically impossible to accurately measure the resin content. Since the impregnated amount of resin is an extremely small amount, the weight of the fiber of a length of a certain extent needs to be measured, and the amount of resin measuring device may enlarge.